The western lowlands of Eritrea are known to have a long history of human settlement. The lowlands have archaeological sites which for long have been associated with the country´s later prehistory. While introducing the potential of the lowlands in light of a multitude of sociocultural processes of the past, an outline of different phases of human settlement constituted in the archaeological record of the region is provided here for the reader.

The archaeology of the western lowlands of Eritrea started to feature since the second half of the last century, when a sizable collection of artifacts was reported from what came to be known as the four Agordat sites. The localities of Kokan, Dandaneit, Shabeit and Ntanei have been designated the Agordat sites and eventually the western lowlands are said to be the conduit of linking this part of the Horn to major civilizations of antiquity in Nubia and ancient Egypt.

Arkell´s report of the Agordat sites in 1942 provoked a significant amount of interest, particularly as to their age and the evidence they possibly provide for cultural contacts between the pastoralists, farmers and urban centers of the Nile Valley and eastern lowlands of Sudan and those of the Eritrean highlands. The Kokan rock shelter was excavated in 1994, 50 years after the initial reporting of the sites and the excavations uncovered flaked stone tools, grindstones, and pottery that helped place the Agordat sites in chronological and cultural sequences. These find showed close similarities to the civilizations which flourished along the Middle Atbara valley and the Gash Delta along the Eritrean- Sudanese borderland. This connection is of paramount importance as it helps understand the emergence of complex agropastoral societies in this part of the Horn.

The evidence from the Agordat sites, and particularly from the Kokan rock shelter, firmly place the western lowlands of Eritrea within the array of regional trading systems from 2300 B.C. to 400 B.C. indicating a successive sequence of human settlement in the lowlands by different cultural groups. The evidence, therefore, indicates that western Eritrea was influenced by a number of nomadic, pastoral and agropastoral cultures from eastern Sudan through direct or indirect contacts. The geographical position of the lowlands also confirms that they could have played an important role in the region as social, economic and political conduits between polities of eastern Sudan and the Nile Valley and the increasingly more complex socio-political systems that emerged in the Eritrean highlands during this period. The premise that the Agordat sites are dated to at least the Egyptian New Kingdom (1500 BC) and that they were tied socially, politically and economically to pastoral, agro-pastoral farming and urban communities as far north as Nubia and perhaps Egypt in itself begs the outline a number of socio-cultural processes that shaped the late prehistory of this part of the Horn.

The northern Horn of Africa had a key position at the junction between two major trade exchange circuits; namely, the Nile Valley and the Red Sea Coast during antiquity. In light of recent researches along the Nile valley and the Red Sea Coast, the western lowlands of Eritrea are considered as crucial interface in the processes of interaction between the Mediterranean and Africa through the circuits. The routes were complementary and sometimes used alternatively in ancient times and trade connections forged along these corridors are important to consider in order to understand the archaeological potential of the western lowlands of Eritrea. Glancing from the wider spectrum, therefore, important milestones of this period are framed here revolving around the peopling of the lowlands and their integration in regional trade to further indicate their archaeological potential.

The peopling of the Eritrean-Sudanese borderland showed a pattern of continuity from the 5th millennium B.C. to the 1st millennium A.D. as shown in the archaeological record of the region. The borderland was inhabited by a cultural group known as the Butana group, which was included in an interchange route starting in the fourth millennium B.C. giving rise to a hierarchical society at the confluence of the Gash and Atbara rivers. A shift to cattle breeding and cereal cultivation was witnessed during this time allowing permanent settlements along the borderland. Later, the progressive shift of the Gash from its original confluence with the Atbara river to the present bed by the late 4th to early 3rd millennium BC allowed a more direct route from the Nile valley to the Horn of Africa, further enabling the descendants of the Butana group to exploit the resources of the western lowlands during seasonal movements from the Gash to the plateau. The descendants, the Gash group as they are called, started to play a crucial role as intermediaries between Nubia and the region of the Horn of Africa and they started to spread along the western lowlands as far as the Red Sea Coast. Residential villages appeared in the middle Barka valley in early second millennium BC along the way from Kassala to the plateau.

As far as interregional trade is concerned two major events which connected the Horn of Africa to the Nile Valley civilizations of Nubia and ancient Egypt can be mentioned. Egyptian commercial expansion southwards began by the fourth millennium BC. The middle Atbara valley and the Horn seem to have been involved in a broad network of contacts by the 3rd and 2nd millennium BC, possibly related to the economic exchange through which ancient Egypt was supplied with African raw materials. The question of the Land of Punt is seen in light of these developments where the Horn of Africa was integrated in the trade connections forged via land caravan routes across the Nile valley.

Throughout the ancient Egyptian history, several nonmilitary expeditions were organized to a region which the Egyptians called Punt. The Land of Punt was a major exporter of gold and biological materials such as myrrh, ebony, ivory, short horned cattle and baboons (Papio hamadryas). The importance of these materials to the ancient Egyptians is reflected in the trade that spanned for 1200 years between ancient Egypt and Punt (2458-1163 BC). Analysis of baboon remains uncovered from New Kingdom tombs, a period considered to be a thriving trade epoch with Punt, showed that the Eritrean corridor was a source of the luxury items to ancient Egypt from the Horn. A further evidence comes from a network of obsidian trade which by the 2nd millennium BC absorbed the western lowlands, Eastern Sudan, the Red Sea Coast and Arabian Peninsula into interregional exchange.

Obsidian raw materials supplied from sources in the Denakil Depression and the Arabian Peninsula circulated along these lands and reached civilizations in Nubia and Egypt via the western lowlands. In this respect, the western lowlands were positioned to reap the benefits of this large circuit of economic interchange that gradually evolved between the peoples of the regions. In conclusion, the Agordat communities should be seen as social, economic and political intermediaries that linked the highlands and lowlands to major civilizations in the Nile valley. The lowlands were isolated towards the end of the 2nd millennium BC as the Red Sea became the main trade route from Egypt to the Horn of Africa and southern Arabia. The shift resulted in regression of social complexity seen in the lowlands and culminated in the emergence of complex societies in highland Eritrea and the Coast, a topic that will be addressed in subsequent editions of the column.